1. Field of the Invention
The present invention relates to an information memory control apparatus which is capable of storing, processing and controlling massive information having a wide variety of attributes and applicable to a variety of electronic publications including electronic catalogues, electronic dictionaries, electronic encyclopedia, etc.
2. Description of the Prior Arts
Recently, reflecting extensively promoted sale of personal computers (PC) in the market, digital processing of a variety of informations has become popular. Also, reflecting the significantly developed auxiliary memory devices, such as floppy disks which are now commercially available at inexpensive prices and optical disks which are now being produced on the commercial basis, the digital processing of a variety of informations has been effectively promoted.
Any of the conventional arts effectively uses limited data-storage area of the auxiliary memory devices under control of the operating system (OS) of computers including personal computers and miniaturized computers by effectively applying the directory structure of the floppy disks used for personal computers for example. Conventionally, any of those auxiliary memory devices is used for provisionally storing digital data. When applying any of those conventional auxiliary memory devices, the operating system merely controls identification of the digital data by putting file names to these data to identify whether each data is a character data composed by a word-processor unit, or a graphic data that should be displayed on a graphic display, or an audio data converted by an analog-digital converter for example, while all of these data are dealt by the operating system without discrimination. Conventionally, all of these data are processed by means of a system hardware which is controlled by microprocessor and a system software processed by an operating system and application programs.
On the other hand, commercial production of the optical disks has made it possible for each disk to store several giga-bytes of data. Typically, the debut of the optical disk has successfully paved the way for applying the disk to the media for storing pulse-code modulated audio data, or for storing character data, or for storing digital image data. This eventually results in the overall growth of the digital audio disks (DAD) represented by the compact disks (CD).
By effectively expanding data-storage capacity of those media mentioned above, modern technology has made it possible to collectively store massive information such as audio signals, characters, pictures, and/or computer software programs in a piece of storage medium.
Referring now to FIG. 6, conventional information memory control apparatuses will be described. Note that if an information had a certain property such as execution of a digital-analog conversion of audio information for example, this property is defined to be an "attribute" in the following description. FIG. 6 is a simplified block diagram of a conventional information memory control apparatus incorporating memory unit 41, data-processing unit 42, operation control unit 43, data-output unit 44, and external memory unit 45.
This external memory unit 45 stores a variety of informations including characters, pictures, and audio signals. These data are delivered from external memory unit 45 to data-output unit 44 in a sequential order shown below. First, data-processing unit 42 controlled by control unit 43 stores designated data from external memory unit 45 in memory unit 41. Next, in response to a command from control unit 43, data-processing unit 42 outputs those data from memory unit 41 to output unit 44. For example, if a character data is designated, a character display is selected as output unit 44, or if a picture data is designated, then a graphic display is selected, conversely, if an audio data is designated, a speaker is selected as output unit 44.
Assume that the conventional information memory control apparatus mentioned above merely transfers a data together with the destination address to the data processor by adding an address of this data processor to the designated data without processing the data itself, then the communication network system has a property which is similar to the above device. More particularly, the conventional information memory control apparatus transfers data from a certain memory device to an aimed data-processor by providing the designated data with addresses of the destination printer, display unit, or any other processors as the attributes so that the destination processor can eventually be allowed to output the designated data after executing necessary processes.
Referring now to FIG. 7, a typical constitution of the conventional communication network system will be described. FIG. 7 is a simplified block diagram showing an example of conventional communication network system incorporating terminal units 51, 52, and 53, switchboards 54, 55, and 56, an external memory device 57, and output units 58 and 59.
First, a consideration is given to the case in which a character data is delivered from external memory device 57 to terminal unit B 52 before displaying the data in a character display unit of output unit B 58. The character data is first provided with the destination address in the terminal unit A 51, where the address itself makes up the attribute of the designated character data. The address-added data is then delivered to the communication line via switchboard A 54. Next, switchboard B 55 identifies that the destination address is the attribute of the designated data corresponds to terminal unit B 52, and then delivers the character data to terminal unit B 52 together with the attribute. Terminal unit B 52 then converts the character data into a character signal and then causes the character signal to be displayed on the output device B 58. When displaying a picture data stored in the external memory device 57 in a graphic display unit of output device C 59 of terminal unit C 53, the picture data is first provided with an attribute whose destination address corresponds to terminal unit C 53, and then the addressed-added picture data is delivered to switchboard A 54 before eventually being displayed on the graphic display.
However, since the constitution of any conventional information memory control apparatus cannot directly select the destination of the data output from external memory unit 45 in response to the attribute of the output data, the memory control apparatus needs to provisionally store the output data in memory unit 41 before allowing data-processing unit 42 to identify the attribute of the output data by a hardware controlled by a microprocessor and a software comprised of an operating system and application programs. Then, the memory control apparatus executes the data processing operation in accordance with the attribute before eventually transmitting the processed data to output unit 44. Thus, in order to correctly deal with massive information, the conventional information memory control apparatus always needs to use a large-capacity memory unit 41, and yet, the apparatus should preliminarily know the information capacity. To properly process information having a variety of attributes, the conventional information memory control apparatus is obliged to use complex data-processing unit 42. Generally, the conventional information memory control apparatus cannot easily execute a real-time data processing operation. In particular, when dealing with audio information, due to the enormous amount of audio signals and continuity of the audio output signals, the conventional apparatus unavoidably faces those problems mentioned above, For example, when dealing with information matching 16-bit quantization, 2-channels, and 44.1 KHz of the sampling specification being exactly identical to those of the audio information stored in a compact disk, the information memory control apparatus needs to transfer information at a rate of 176 Kbytes/second. Obviously, the conventional apparatus needs to use a large- capacity memory unit 41 in order to transmit information to the D/A converter on the real-time basis using those conventional techniques mentioned above. Furthermore, when operating the conventional communication network system, information stored in the external memory device 57 is not provided with any attribute. To compensate for this, it is necessary for the system to compulsorily add the attribute inside of the terminal unit A 51. In other words, basically, the conventional communication network system unavoidably needs to add the attribute to information inside of the external memory device 57 by applying hardware and software inside of the terminal unit A 51.
In addition, basically, each terminal unit of the conventional communication network system makes up an independent data-processing unit, and thus, the system needs to set up a specific communication rule(protocol) for transmitting and receiving information between terminal units, which in turn unavoidably expands the size of the hardware at the part of the interfaces of terminal units. Furthermore, general-purpose utility is particularly urged for the communication network. On the other hand, the presence of the protocol itself causes the system to unavoidably execute sophisticated processes using both hardware and software in accordance with the established protocol in addition to the proper information processing such as the D/A conversion process inherently needed for processing audio signals for example. This is certainly a grave problem from the viewpoint of the actual need for directly transferring the designated data from memory device to a device corresponding to the attribute of the data.